First off, I don't think the double standard is nearly as pervasive as others might imply. Aside from the FCC (which was created initially to deal with radio liscensing and broadcasts), the ability of society to self-regulate depictions of both sex and violence has put both of them on a bit of an equal path. Movies receive R ratings for either violence or sex. Video games receive Mature ratings for the same things. Personally, in my own creations, I tend to treat sex and violence with a double-standard. It's not because I'm a prude (shah! Me!), but because I think there's a fundamental difference in how the average person reacts to the depiction of sex, and the depiction of violence, in a story. I'll explain in greater detail behind the cut.
My original reasons for not including nudity in Better Days was to help me show others that I could develope the characters I wanted and tell stories and try to foster the interest of a reader base without relying on pornography as a crutch. Since then, there have been stories that have had both violence, implied sex, and sexy (if not nude) depictions of some characters. I've seen a lot of reactions to each and every circumstance, and I think I have a pretty good idea of how people respond to both violence and sex on a psychological level. At least, a large number of them.
I'll submit to you, something I've noticed about how people approach sex and violence in a story: No one's ever written me an e-mail telling me that they think that the way I drew someone getting shot with a shotgun, or getting their head cracked with a baseball bat, was really good and they wondered when I'd write another story with similar violence in it. Never. Not once. If I make a serious story that depicts serious violence as a product of the story's plot, then it seems to be taken at face-value by the readers. It tends to be taken with the seriousness that it deserves and that's expected of the situation. I've never really been accused to condoning gratuitous, careless violence. I've never been accused of inserting violence into my stories as a means of pleasing my own sense of bloodlust or living out my rage at the world through vicarious means. Never. Not once. Sex is a completely different story.
People's maturity level seems to plummet substantially when sex is depicted with the same seriousness, in a serious story, as violence. If you put together a serious story about seriously damaged people with a theme that displays a serious consequence of bad sexual decisions, or sexual acts that are the product of a plotline, the readers seem to have this power to extract the sexual situation from the context of the story all together and start to draw seriously flawed conclusions about the sex that's being shown, or the proclivities of the author. The titilating factor of any mention or hint of sex seems to throw them into another level of consciousness where they can draw an alternate form of entertainment from the sexual situation that can be entirely divorced from the theme of the story where the sex takes place. This is what I've concluded from just my own comic where I don't even show naked bits. If I coupled my stories with nudity and explicite sex, I can easily imagine how much worse it would be, and how much of a distracting affect it would have on the stories. As it is, it's entirely unnecessary for the telling of the story and would simply ammount to "fan-service", a completely alternate form of entertainment outside of the primary focus of the story and characters. I'll also re-iterate a point by saying that no one has ever browsed my archive, flipping from page to page, ignoring plot, text, and character development, looking for the snapshots of gratuitous violence. Think about it.
I've never received more vitriolic hate mail about anything I've ever written about or drawn, than what I received over the depiction of implied sex between Fisk and Lucy. It's true. People swore they'd never read the comic again. They said I'd ruined everything for them. It was soiled, destroyed, the comic was going down pathways they couldn't abide with, completely ignoring the context of the situation and not bothering to stick around to see the what would happen as a consequence. They didn't stop to think that I was depicting a dysfunctional act that would have serious consequences to the characters as they developed throughout their lives. It was sex, and therefor treated as sexual entertainment, a "kink" they didn't agree with, the author condoning the behavior and infusing it into his stories for his own perverted gratification. A lot of it is based on an entirely different reaction from others, where instead of disdain, they crave it. They go off the deep end to express their juvanile fixation on anything sexual and soak it up with squirming glee despite the context in which it's depicted.
I don't know if there's some psychological triggers that work differently for violence and sex, but whatever the reasons, this is just what I've observed. I think a lot of it has to do with the fact that the consequences of poor sexual decisions are much harder to extrapolate from stories and events, than the stark, obvious consequences of extreme violence. Sexual reprecussions lead to psychological damage, developmental issues, and the inability to foster future relationships in a healthy way. These are all non-immediate issues that are hard to express within a few pages of story, and have to be depicted over the span of a person's life. I also think that most healthy people have a much greater, instinctive drive to find sexual gratification and titilation, than they do a drive to express themselves with acts of physical violence. That, in and of itself, makes the depiction of sex more powerful than the depiction of violence, I think. But overall, the reason I don't depict nudity and explicite sex in Better Days is because I think it would distract and be an unnecessary indulgence. It could quickly become the fixation of a large number of readers and it'd make it even more difficult to keep people's minds fixed on the more important things in the story.
I guess my advice would be, if your primary focus is going to be sex, then by all means, go all the way. If yoru primary focus is the storytelling and character development in all situations, not just sex, I'd shy away from that kind of gratuity.